L.B. Jeffries has a nice essay up on the idea of 'games as languages' — a combination of coercing players to take certain actions and encouraging certain responses, creating a dialogue of sorts. As Jeffries says, "It’s not exactly talking to another person…but it’s not just rolling dice or pressing shoot either." As games get more complex, so does the 'language' aspect — choices are expressive elements, and the more choices one has, the more opportunities for unique combinations. Even the simplest of games involves communication — 'go here, do that.' With the influx of more diverse and user-created building blocks, it seems reasonable that the 'languages' would begin to emerge more clearly:

There are dozens of ways to express the same thing in a language, depending on the circumstances and ways the speaker wishes to interact with their surroundings. In comparison, video games have far less choices but that does not rule out calling them ‘tiny languages’. Their size then being directly proportional to the number of options given to a player. It can be tough to pick up on this in a mostly linear game like God of War because it has so few options that one can’t really appreciate the ‘games as language’ argument. That’s a game that falls under Hideo Kojima’s ‘games as museums’ design theory, and is more about delivering a series of set experiences that the player roleplays through. On the other hand, games such as Grand Theft Auto IV and Far Cry 2 on a greater level represent enough choices compounded together that the first indications of a language start to form.

Jeffries notes in the comments that this is sort of the converse of something that Ian Bogost has written extensively on — the ability of games to communicate at masses of people. Games as Language Systems [PopMatters]